Converse used to have a plant and outlet store down in Malden, Ma just a mile or so down the road from where I lived in Everett. You could get their shoes there dirt cheap, even during the early 80's hey days of their shoes
In the store they had a few sneakers on display of those used by the pros. Bill had a pair there but so did Bob Lanier who I think had a size 24 foot. Those sneakers were massive. As a kid I was always amazed that someone could have a foot that big.